Thermochromic efficiency indicator



FIG. 1 is a top and right side perspective view of a thermochromic efficiency indicator, embodying our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines shown are included for the purpose of illustrating the unclaimed portions of the article and form no part of the claim. 

CLAIM The ornamental design for a thermochromic efficiency indicator, as shown and described. 